The key step to installing a successful tile floor or wall finish is choosing the correct thinset and applying it the correct way. Poorly applied mortar will result in tiles not having proper adhesion, which will cause the tiles come loose over time. Poly-modified Thin Set Mortars will always ensure better adhesion, even for ceramic tiles, but are more costly. If using standard un-modified Thin set mortars, the mortar may eventually crack, which will result in tiles coming off prematurely. If you’re on a budget, you can purchase an unfortified adhesive and just add liquid latex to it according to its instructions. Otherwise, you can purchase an already polymer fortified adhesive and just add water to it as directed.